Temat: remote sensing algorithm - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Spectra of light absorption by phytoplankton pigments in the Baltic; conclusions to be drawn from a Gaussian analysis of empirical data
Autorzy:: Ficek, D.
Kaczmarek, S.
Ston-Egiert, J.
Wozniak, B.
Majchrowski, R.
Dera, J.
Powiązania:: https://bibliotekanauki.pl/articles/47835.pdf
Data publikacji:: 2004
Wydawca:: Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:: phytoplankton pigment
remote sensing algorithm
Baltic Sea
Gaussian analysis
light absorption
Opis:: Analysed by differential spectroscopy, 1208 empirical spectra of light absorption apl(λ) by Baltic phytoplankton were spectrally decomposed into 26 elementary Gaussian component bands. At the same time the composition and concentrations of each of the 5 main groups of pigments (chlorophylls a, chlorophylls b, chlorophylls c, photosynthetic carotenoids and photoprotecting carotenoids) were analysed in 782 samples by HPLC. Inspection of the correlations between the intensities of the 26 elementary absorption bands and the concentrations of the pigment groups resulted in given elementary bands being attributed to particular pigment groups and the spectra of the mass-specific absorption coefficients established for these pigment groups. Moreover, balancing the absorption effects due to these 5 pigment groups against the overall absorption spectra of phytoplankton suggested the presence of a sixth group of pigments, as yet unidentified (UP), undetected by HPLC. Apr eliminary mathematical description of the spectral absorption properties of these UP was established. Like some forms of phycobilins, these pigments are strong absorbers in the 450–650 nm spectral region. The packaging effect of pigments in Baltic phytoplankton was analysed statistically, then correlated with the concentration of chlorophyll a in Baltic water. As a result, a Baltic version of the algorithm of light absorption by phytoplankton could be developed. This algorithm can be applied to estimate overall phytoplankton absorption spectra and their components due to the various groups of pigments from a knowledge of their concentrations in Baltic water.
Źródło:: Oceanologia; 2004, 46, 4
0078-3234
Pojawia się w:: Oceanologia
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:: Testing the performance of empirical remote sensing algorithms in the Baltic Sea waters with modelled and in situ reflectance data
Autorzy:: Ligi, M.
Kutser, T.
Kallio, K.
Attila, J.
Koponen, S.
Paavel, B.
Soomets, T.
Reinart, A.
Powiązania:: https://bibliotekanauki.pl/articles/48045.pdf
Data publikacji:: 2017
Wydawca:: Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:: remote sensing
algorithm
Baltic Sea
coastal water
chlorophyll a
optical property
phytoplankton assemblage
water reflectance
Opis:: Remote sensing studies published up to now show that the performance of empirical (band-ratio type) algorithms in different parts of the Baltic Sea is highly variable. Best performing algorithms are different in the different regions of the Baltic Sea. Moreover, there is indication that the algorithms have to be seasonal as the optical properties of phytoplankton assemblages dominating in spring and summer are different. We modelled 15,600 reflectance spectra using HydroLight radiative transfer model to test 58 previously published empirical algorithms. 7200 of the spectra were modelled using specific inherent optical properties (SIOPs) of the open parts of the Baltic Sea in summer and 8400 with SIOPs of spring season. Concentration range of chlorophyll-a, coloured dissolved organic matter (CDOM) and suspended matter used in the model simulations were based on the actually measured values available in literature. For each optically active constituent we added one concentration below actually measured minimum and one concentration above the actually measured maximum value in order to test the performance of the algorithms in wider range. 77 in situ reflectance spectra from rocky (Sweden) and sandy (Estonia, Latvia) coastal areas were used to evaluate the performance of the algorithms also in coastal waters. Seasonal differences in the algorithm performance were confirmed but we found also algorithms that can be used in both spring and summer conditions. The algorithms that use bands available on OLCI, launched in February 2016, are highlighted as this sensor will be available for Baltic Sea monitoring for coming decades.
Źródło:: Oceanologia; 2017, 59, 1
0078-3234
Pojawia się w:: Oceanologia
Dostawca treści:: Biblioteka Nauki